Evaluation of transmission line insulator for I-Type string insulator design

Glazed glass cap and pin insulators that have been removed from the transmission line, have electrical characteristics ensuring them to be reused and reinstalled on lower voltage distribution level lines. The electrical properties determination involving insulator resistance, self-capacitance, corona inception voltage and flashover voltage were measured using AC high voltage generating unit. The advantage of this paper is that it presents, an effective new technique to select aged glazed glass insulator based on measured characteristics, in combination with likelihood of flashover occurrence and compatibility factor, making I-type string insulator design more deterministically and particularly for 33kV distribution line application. Using technique employing coefficient of compatibility, it was found that transmission line glazed glass cap and pin insulator can be recycled, selected and reused for distribution line insulation application.